There’s a reason that audiences are walking out of “Contagion” with their nerves jangled, says director Steven Soderbergh: it’s got all the elements of a horror film, even if the boogeyman is a microscopic virus.

“I always thought of it as a modern horror film.”– I really did,” Soderbergh tells PopcornBiz. “I mean, if a horror movie is designed to scare you I certainly thought that there were things in this that were scary.”

The filmmaker says that once he heard screenwriter Scott Z. Burns’ startlingly realistic take on the potentially catastrophic nature of a mysterious global virus, he recognized the cinematic scare factors – and so did the studio, Warner Bros., and the Soderbergh-style all-star ensemble (including Matt Damon, Kate Winslet, Gwyneth Paltrow, Lawrence Fishbourne, Marion Cotillard and Jude Law) who signed on to bring the tale to life.

“Everyone felt there was a place for an ultra-realistic film about this subject,” says the director. “Nobody hesitated. It all happened very quickly, uncharacteristically quickly actually considering what the business is right now for adult dramas. So that made me feel like maybe we’re on to something.”

With the global scope of the film and the multi-character aspect, Soderbergh imposed some storytelling rules to keep the tale from blowing up into empty spectacle. “We were trying to have it be epic and also intimate at the same time,” he says. “The one rule that we had was that we can’t go anywhere where one of our characters hasn’t been. We can’t cut to a city or a group of extras that we’ve never been to, that we don’t know personally. That was our rule. And that’s a pretty significant rule to adhere to in a movie in which you’re trying to give a sense of something that’s happening on a large scale, but we felt that all of the elements that we had issues with prior when we see any kind of disaster film we’re sort of centered around that idea. That suddenly you cut to Paris where you’ve never been and something happens and it’s a bunch of people you have no emotional engagement with.”

Even after taking such a hands-on approach to the germophobe’s nightmare scenario, Soderbergh says he’s not overloading on the Purell. “I don’t know if my behavior has changed,” he admits. “I’m just really aware of it now. I’m aware of the fact that I was handed some lip balm by one of the makeup people, which I took a Kleenex to and cleaned off – but who knows if that worked, so don’t get near my mouth. Having gone through it, I’m always going to be conscious of it now. It was fun during the preview to watch the lights come up and four hundred people realize that they’re next to a bunch of strangers and that they’ve touched everything. You could tell they weren’t happy.”